Bennu, a giant asteroid, may be headed for Earth in 2135. NASA says it can do nothing.

"I would rather be ashes than dust!\r\nI would rather be a superb meteor, every atom of me in magnificent glow,\r\nthan a sleepy and permanent planet."\r\n — Jack London

There are a number of ways to affect the path of an asteroid—especially one that’s likely to cause massive destruction to Earth. 

Enter Bennu, an asteroid as tall as the Empire State Building, but even more massive because it’s round. If it plunged into our planet, the effects would be absolutely catastrophic no matter the point of impact. As of right now, the chances that it will do just that are 1 in 2,600; these numbers get refined as time goes on and the potential event gets closer. 

The year 2135 is what NASA is looking at for it to encounter Earth, if it’s actually going to. There is talk of launching a rocket to "nudge" it out of its current path; scientists based at the Lawrence Livermore National Laboratory have been studying, with NASA, the possibility of on a spacecraft they would call HAMMER (Hypervelocity Asteroid Mitigation Mission for Emergency Response vehicle), but that looks like it would have no effect on something this size. Another possible way to affect the trajectory of an asteroid is to send up satellites to travel alongside the object, using gravitational pull to alter its path. Again, that won't work with this behemoth.

One of the only ways to deal with a rock the size of Bennu, then, is a nuclear warhead; that’s not preferred by scientists because there’s a good chance it would rain radioactive stones and chunks right back into our atmosphere. 

With enough time—in Bennu’s case, over 100 years—perhaps a better solution will be developed, but the fact remains: we’re vulnerable to such objects ramming into us, and we don’t have a lot of great options to prevent it. 

It is, after all, what caused dinosaurs to go extinct, and the cosmic shooting gallery that we live in hasn't gone away. 

How to make a black hole

Here's the science of black holes, from supermassive monsters to ones the size of ping-pong balls.

  • There's more than one way to make a black hole, says NASA's Michelle Thaller. They're not always formed from dead stars. For example, there are teeny tiny black holes all around us, the result of high-energy cosmic rays slamming into our atmosphere with enough force to cram matter together so densely that no light can escape.
  • CERN is trying to create artificial black holes right now, but don't worry, it's not dangerous. Scientists there are attempting to smash two particles together with such intensity that it creates a black hole that would live for just a millionth of a second.
  • Thaller uses a brilliant analogy involving a rubber sheet, a marble, and an elephant to explain why different black holes have varying densities. Watch and learn!
  • Bonus fact: If the Earth became a black hole, it would be crushed to the size of a ping-pong ball.

Project 100,000: The Vietnam War's cruel and deadly experiment

Military recruits are supposed to be assessed to see whether they're fit for service. What happens when they're not?

Flickr user Tommy Truong79
Politics & Current Affairs
  • During the Vietnam War, Robert McNamara began a program called Project 100,000.
  • The program brought over 300,000 men to Vietnam who failed to meet minimum criteria for military service, both physically and mentally.
  • Project 100,000 recruits were killed in disproportionate numbers and fared worse after their military service than their civilian peers, making the program one of the biggest—and possibly cruelest—mistakes of the Vietnam War.
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China’s artificial sun reaches fusion temperature: 100 million degrees

In a breakthrough for nuclear fusion research, scientists at China's Experimental Advanced Superconducting Tokamak (EAST) reactor have produced temperatures necessary for nuclear fusion on Earth.

Credit: EAST Team
Surprising Science
  • The EAST reactor was able to heat hydrogen to temperatures exceeding 100 million degrees Celsius.
  • Nuclear fusion could someday provide the planet with a virtually limitless supply of clean energy.
  • Still, scientists have many other obstacles to pass before fusion technology becomes a viable energy source.
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